Sensitive Detection of SARS-CoV-2 Using a Novel Plasmonic Fiber Optic Biosensor Design

The coronavirus (COVID-19) pandemic has put the entire world at risk and caused an economic downturn in most countries. This work provided theoretical insight into a novel fiber optic based plasmonic biosensor that can be used for sensitive detection of SARS-CoV-2. The aim was always to achieve reliable, sensitive and reproducible detection. The proposed configuration is based on Ag–Au alloy nanoparticles films covered with a layer of graphene which promotes the molecular adsorption and a thiol-tethered DNA layer as a ligand. Here the combination of two recent approaches in a single configuration is very promising and can only lead to considerable improvement. We have theoretically analyzed the sensor performance in terms of sensitivity and resolution. To highlight the importance of the new configuration, a comparison was made with two other sensors. One is based on gold nanoparticles incorporated into a host medium, the other is composed of a bimetallic Ag-Au layer in the massive state. The numerical results obtained has been validated and show that the proposed configuration offers better sensitivity (7100 nm\RIU) and good resolution (figure of merit; FOM=38.88Tand signal-to-noise ratio; SNR=0.388). In addition, a parametric study was performed such as the graphene layers number and the size of the nanoparticles.

Effect of axial coordination environment on quantum tunnelling magnetization for dysprosium single ion magnet with theoretical insight

Herein, we report two mononuclear Dysprosium complexes [Dy(H4L){B(OMe)2(Ph)2}2](Cl)∙MeOH (1), and [Dy(H4L){MeOH)2(NCS)2](Cl) (2) (where H4L = 2,2′-(pyridine-2,6-diylbis(ethan-1-yl-1-ylidene))bis(N-phenylhydrazinecarboxamide) with different axial coordination environment. The structural analysis revealed that the pentadentate H4L ligand...

Theoretical insight into density and stability differences on RDX, HMX and CL-20

yclic nitramine explosives including RDX, HMX and CL-20 have drawn extensive researches due to their wide applications and excellent performances. However, these three nitramine explosives exhibit obviously different properties (such...